Stains & molecular markers
LEF1


Topic Completed: 29 September 2020

Minor changes: 1 October 2020

Copyright: 2020, PathologyOutlines.com, Inc.

PubMed Search: LEF1 [title] pathology

Alessandra C. Schmitt, M.D.
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Cite this page: Schmitt AC. LEF1. PathologyOutlines.com website. https://www.pathologyoutlines.com/topic/stainsLEF1.html. Accessed December 4th, 2020.
Definition / general
  • Lymphoid enhancer binding factor 1 (LEF1) is a transcription factor for B and T cells and is involved in the Wnt / CTNNB1 pathway which regulates normal development of airway submucosal glands, mammary glands, teeth and adnexal structures (Nat Rev Immunol 2005;5:21, Development 1999;126:4441)
Essential features
  • Not specific
  • Helpful when used as a panel
  • Positive staining favors:
    • Pleomorphic adenoma, basal cell adenoma or basal cell adenocarcinoma over adenoid cystic carcinoma
    • Chronic lymphocytic B cell leukemia / small lymphocytic lymphoma over other small B cell lymphomas
    • Cribriform morular variant of papillary thyroid carcinoma over other papillary thyroid carcinoma variants
    • Solid pseudopapillary tumor over pancreatic neuroendocrine carcinoma or pancreatic adenocarcinoma
Interpretation
  • Nuclear stain
Uses by pathologists
Prognostic factors
Microscopic (histologic) description
  • Focal staining with peripheral accentuation possible in basal cell adenoma and pleomorphic adenoma (shown in figures below)
  • Positive staining in pleomorphic adenoma is not specific
Microscopic (histologic) images

Contributed by Alessandra C. Schmitt, M.D.
Basal cell adenoma

Basal cell adenoma

LEF1 positive basal cell adenoma

LEF1, basal cell adenoma

Positive staining - normal
Positive staining - disease
Negative staining
Board review style question #1

A 50 year old woman presented with an infiltrative left submandibular mass. LEF1 stain was performed and was negative. The tumor is best diagnosed as

  1. Adenoid cystic carcinoma
  2. Basal cell adenocarcinoma
  3. Basal cell adenoma
  4. Cellular pleomorphic adenoma
Board review answer #1
A. Adenoid cystic carcinoma

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Reference: LEF1
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